Chair with flex member

ABSTRACT

A chair includes a first side member, a second side member, a back cross member, a first flex member, and a second flex member. The first side member supports a first side of the chair and the second side member supports a second side of the chair. The back cross member is situated between the first side member and the second side member and rotates relative to the first side member and the second side member. The first flex member is coupled to the first side member and the back cross member and twists as the back cross member rotates relative to the first side member and the second side member. The second flex member is coupled to the second side member and the back cross member and twists as the back cross member rotates relative to the first side member and the second side member.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority to U.S. Provisional Application No. 62/007,591, filed on Jun. 4, 2014, entitled CHAIR WITH FLEX MEMBER, which is herein incorporated by reference in its entirety.

BACKGROUND

Chair manufacturers continually strive to improve the comfort, benefits, aesthetics, manufacturability, and utility of the chairs they produce. Some chairs have features, such as armrests and a reclining back, for comfort and support. Some chairs have features, such as folding seats, to occupy less space. Folding seats can be used in office or residential settings, on buses to make room for equipment, such as wheelchairs or bicycles, in cars to provide extra seating, and in stadiums and auditoriums to facilitate ingress and egress from the seating area, for example.

SUMMARY

Some embodiments described in this disclosure relate to a chair that includes a first side member, a second side member, a back cross member, a first flex member, and a second flex member. The first side member supports a first side of the chair on a surface and the second side member supports a second side of the chair on the surface. The back cross member is situated between the first side member and the second side member and rotates relative to the first side member and the second side member. The first flex member is coupled to the first side member and the back cross member, and the first flex member twists as the back cross member rotates relative to the first side member and the second side member. The second flex member is coupled to the second side member and the back cross member, and the second flex member twists as the back cross member rotates relative to the first side member and the second side member.

Some embodiments relate to a chair where the first flex member is a first torsion spring that twists as the back cross member rotates relative to the first side member and the second side member and the second flex member is a second torsion spring that twists as the back cross member rotates relative to the first side member and the second side member.

Some embodiments relate to a chair where the back cross member has a cross member longitudinal axis and the back cross member rotates relative to the first side member and the second side member around the cross member longitudinal axis. Some embodiments relate to a chair where the first flex member has a flex member longitudinal axis that is parallel with the cross member longitudinal axis and the first flex member twists around the flex member longitudinal axis as the back cross member rotates around the cross member longitudinal axis.

Some embodiments described in this disclosure relate to a chair that includes a first side member, a second side member, a back cross member, a first flex member, and a second flex member. The first side member supports a first side of the chair on a surface and the second side member supports a second side of the chair on the surface. The back cross member is situated between the first side member and the second side member and the back cross member rotates relative to the first side member and the second side member. The first flex member is secured to the first side member with at least one first fastener and the first flex member twists as the back cross member rotates relative to the first side member and the second side member. The second flex member is secured to the second side member with at least one second fastener and the second flex member twists as the back cross member rotates relative to the first side member and the second side member. The back cross member rotates and the at least one first fastener provides a first stop against the back cross member and the at least one second fastener provides a second stop against the back cross member to substantially prevent further rotation of the back cross member.

Some embodiments relate to a method of making a chair, which includes: fastening a first flex member to a first side member; fastening a second flex member to a second side member; and securing a chair back to a back cross member. Where securing the chair back to the back cross member couples the chair back to the first flex member and the second flex member. Some embodiments relate to a method that includes fitting a first portion of the first flex member into the first side member prior to fastening the first flex member to the first side member. Some embodiments relate to a method that includes fitting a second portion of the first flex member into the back cross member prior to securing the chair back to the back cross member.

Some embodiments described in this disclosure relate to a chair that includes a base, a seat maintained by the base, a chair back, and a chair back flex assembly. The base is configured to support the chair on a surface and has a first side and a second side. The chair back has a reclined position and an upright position and the chair back flex assembly couples the chair back to the base. The chair back flex assembly includes a back cross member and a first flex member. The back cross member has a first end and a second end and a longitudinal axis and the first flex member is coupled to the back cross member at the first end of the back cross member such that the first flex member elastically deflects to permit rotation of the back cross member about the longitudinal axis of the back cross member as the chair back is moved from the upright position to the reclined position. Some embodiments relate to a chair including a second flex member coupled to the back cross member at the second end of the back cross member such that the second flex member elastically deflects to permit rotation of the back cross member about the longitudinal axis of the back cross member as the chair back is moved from the upright position to the reclined position.

While multiple embodiments are disclosed, still other embodiments of the present invention will become apparent to those skilled in the art from the following detailed description, which shows and describes illustrative embodiments of the invention. Accordingly, the drawings and detailed description are to be regarded as illustrative in nature and not restrictive.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagram illustrating a perspective view of a chair, according to some embodiments.

FIG. 2 is a diagram illustrating a side view of the chair of FIG. 1, according to some embodiments.

FIG. 3 is a diagram illustrating a top view of the chair of FIG. 1, according to some embodiments.

FIG. 4 is a diagram illustrating a front view of the chair of FIG. 1, according to some embodiments.

FIG. 5 is a diagram illustrating a back view of the chair of FIG. 1, according to some embodiments.

FIG. 6 is a diagram illustrating an enlarged view of a chair back attached to a chair back flex assembly, according to some embodiments.

FIG. 7 is a cross-section diagram taken along the line A-A in FIG. 6 and illustrating the chair back attached to the chair back flex assembly, which is attached to the first side member on the first side of the chair, according to some embodiments.

FIG. 8 is a diagram illustrating a perspective view of the back of the first flex member, according to some embodiments.

FIG. 9 is a diagram illustrating a perspective view of the front of the first flex member, according to some embodiments.

FIG. 10 is a diagram illustrating an enlarged front view of the first side of the chair without the chair back, according to some embodiments.

FIG. 11 is a diagram illustrating an enlarged back view of the first side of the chair including the chair back, according to some embodiments.

FIG. 12 is a cross-section diagram of the first side of the chair taken along the line B-B in FIG. 11 and illustrating fasteners securing the first flex member to the first side member, according to some embodiments.

FIG. 13 is a cross-section diagram of the first side of the chair taken along the line C-C in FIG. 11 and illustrating the attachment member coupling the chair back to the back cross member and the first flex member, according to some embodiments.

FIG. 14 is a cross-section diagram of the first side of the chair taken along the line D-D in FIG. 11 and illustrating the first front leg connected to the first leg extension, which is attached to the first back leg, according to some embodiments.

FIG. 15 is a diagram illustrating a bottom perspective view of the chair of FIG. 1, according to some embodiments.

FIG. 16 is a diagram illustrating a bottom view of the chair of FIG. 1, according to some embodiments.

FIG. 17 is a diagram illustrating the chair of FIG. 1 including a seat that rotates between the down position for sitting on and the upright position for saving space and storage, according to some embodiments.

FIG. 18 is a diagram illustrating a perspective view of a chair 200, according to some embodiments.

FIG. 19 is a diagram illustrating a side view of the chair of FIG. 18, according to some embodiments.

FIG. 20 is a diagram illustrating a top view of the chair of FIG. 18, according to some embodiments.

FIG. 21 is a diagram illustrating a front view of the chair of FIG. 18, according to some embodiments.

FIG. 22 is a diagram illustrating a back view of the chair of FIG. 18, according to some embodiments.

FIG. 23 is a diagram illustrating a bottom perspective view of the chair of FIG. 18, according to some embodiments.

FIG. 24 is a diagram illustrating a bottom view of the chair of FIG. 18, according to some embodiments.

FIG. 25 is a diagram illustrating the chair of FIG. 18 including a seat that rotates between the down position for sitting on and the upright position for saving space and storage, and the first and second armrests that rotate between a down position and an upright position, according to some embodiments.

FIG. 26 is a diagram illustrating chairs stacked for storage, according to some embodiments.

FIG. 27 is a diagram illustrating chairs aligned in a row for storage, according to some embodiments.

FIG. 28 is a flowchart diagram illustrating a method of building a chair, according to some embodiments.

DETAILED DESCRIPTION

FIGS. 1-6 are diagrams illustrating a chair 40 that includes a chair back 42 that flexes for comfort, according to some embodiments described in the disclosure. The chair 40 is a lightweight, armless chair that includes a base 44, a seat 46, and the chair back 42. The chair back 42 has an upright position and a reclined position that is illustrated in dashed lines in FIG. 2. The chair back 42 flexes backward toward the reclined position as a user leans back in the chair 40 and the chair back 42 returns to the upright position when the user stops leaning back in the chair 40. In some embodiments, the chair 40 includes armrests.

FIG. 1 is a diagram illustrating a perspective view of the chair 40, according to some embodiments, and FIG. 2 is a diagram illustrating a side view of the chair 40, according to some embodiments. The base 44 supports the chair 40 on a surface, such as the floor, and the base 44 maintains the seat 46 and the chair back 42 off the surface. The base 44 includes a first side member 48 at a first side 50 of the chair 40 and a second side member 52 at a second side 54 of the chair 40. The first side member 48 supports the first side 50 of the chair 40 on the surface and the second side member 52 supports the second side 54 of the chair 40 on the surface. The first side member 48 is coupled to the second side member 52 to support the seat 46 and the chair back 42.

The first side member 48 includes a first front leg 56 and a first back leg 58 and the second side member 52 includes a second front leg 60 and a second back leg 62. The first front leg 56 has a rounded curve shape and is coupled at one end to the first back leg 58 and curves forward toward the surface at the front of the chair 40. The first back leg 58 has a slightly rounded curve shape and is coupled to the one end of the first front leg 56 and curves from the coupling toward the surface at the back of the chair 40. The second front leg 60 has a rounded curve shape and is coupled at one end to the second back leg 62 and curves forward toward the surface at the front of the chair 40. The second back leg 62 has a slightly rounded curve shape and is coupled to the one end of the second front leg 60 and curves from the coupling toward the surface at the back of the chair 40.

Each of the legs 56, 58, 60, and 62 is attached to a corresponding wheel or caster 64, 66, 68, and 70 near the surface. The wheels or casters 64, 66, 68, and 70 roll on the surface, such that the chair 40 can be rolled from one place to another place on the surface. In some embodiments, each of the legs 56, 58, 60, and 62 includes a leg stub or cover at the surface to maintain the chair 40 in one place after it has been placed in position on the surface.

The seat 46 is coupled to the first side member 48 and the second side member 52 via a seat support assembly 72 (shown in FIG. 2) and the chair back 42 is coupled to the first side member 48 and the second side member 52 via a chair back flex assembly 74 (shown in FIG. 2). In some embodiments, the seat 46 folds into an upright position to save space and for storing the chair 40.

FIG. 3 is a diagram illustrating a top view of the chair 40, according to some embodiments, and FIG. 4 is a diagram illustrating a front view of the chair 40, according to some embodiments. As shown in at least FIGS. 3 and 4, the first front leg 56 is coupled to the first back leg 58 by a first leg extension 76 and the second front leg 60 is coupled to the second back leg 62 by a second leg extension 78. The first leg extension 76 is securely attached to the first back leg 58 and extends from the first back leg 58 toward the middle or a centerline 80 of the chair 40. The first front leg 56 is securely attached to the first leg extension 76 inside the first back leg 58, toward the centerline 80 of the chair. The second leg extension 78 is securely attached to the second back leg 62 and extends from the second back leg 62 toward the centerline 80 of the chair 40. The second front leg 60 is securely attached to the second leg extension 78 inside the second back leg 62, toward the centerline 80 of the chair. The first side member 48 includes the first front leg 56, the first back leg 58, and the first leg extension 76. The second side member 52 includes the second front leg 60, the second back leg 62, and the second leg extension 78.

FIG. 5 is a diagram illustrating a back view of the chair 40, according to some embodiments, and FIG. 6 is a diagram illustrating an enlarged view of the chair back 42 attached to the chair back flex assembly 74, according to some embodiments.

The chair 40 includes the chair back 42 coupled to the base 44 by the chair back flex assembly 74. The chair back 42 includes a chair back frame 82 and back support material 84. The chair back frame 82 is a rigid frame that includes a lower crossbar member 86, two upright members 88 and 90 that extend vertically from the lower crossbar member 86, and an upper crossbar member 92 that connects the two upright members 88 and 90 at the top of the chair back 42. The back support material 84 is attached to the chair back frame 82, including the lower crossbar member 86, the two upright members 88 and 90, and the upper crossbar member 92, to support the back of the user. In some embodiments, the chair back frame 82 is made from a rigid material, such as plastic or metal. In some embodiments, the chair back frame 82 is not a closed curve shape. In some embodiments, the chair back frame 82 is a different shape having one or two upright frame members attached to a lower crossbar member, but without an upper crossbar member.

The chair back flex assembly 74 includes a back cross member 94, a first flex member 96, and a second flex member 98. The back cross member 94 includes a first end 100, a second end 102, and a cross member longitudinal axis 104. The first flex member 96 is coupled to the back cross member 94 at the first end 100 and the second flex member 98 is coupled to the back cross member 94 at the second end 102. Also, the first flex member 96 is coupled to the first leg extension 76 of the first side member 48 and the second flex member 98 is coupled to the second leg extension 78 of the second side member 52, such that the back cross member 94 is situated between the first side member 48 and the second side member 52.

The chair back 42 is coupled to the chair back flex assembly 74 by the lower crossbar member 86, and the chair back flex assembly 74 couples the chair back 42 to the first side member 48 and the second side member 52 of the base 42. The lower crossbar member 86 of the chair back frame 82 is coupled to the back cross member 94 and to each of the first and second flex members 96 and 98 of the chair back flex assembly 74. The back cross member 94 fits into a slot in the lower crossbar member 86, such that the lower crossbar member 86 fits around the back cross member 94. As seen from the front of the chair 40, the lower crossbar member 86 covers the front of the back cross member 94 and front portions of the first and second flex members 96 and 98. As seen from the back of the chair 40, the lower crossbar member 86 leaves the back of the back cross member 94 and back portions of the first and second flex members 96 and 98 uncovered, where a bottom portion 86 a of the lower crossbar member 86 extends below the back cross member 94 and an upper portion 86 b of the lower crossbar member 86 extends above the back cross member 94. The bottom portion 86 a of the lower crossbar member 86 includes four connection blocks 106 a-106 d. Attachment members (not shown in FIG. 6) pass through the upper portion 86 b of the lower crossbar member 86 and the back cross member 94 and into the four connection blocks 106 a-106 d to secure the chair back 42 to the chair back flex assembly 74. The attachment member secured into connection block 106 a also passes through the first flex member 96, which is inserted into the back cross member 94, and the attachment member secured into connection block 106 d also passes through the second flex member 96, which is inserted into the back cross member 94.

In operation, the chair back 42 is moved between the upright position and the reclined position, such that the top 108 of the chair back 42 moves backward and forward and the back cross member 94 rotates around or about the cross member longitudinal axis 104. The first flex member 96 and the second flex member 98 twist as the back cross member 94 rotates relative to the stationary first and second side members 48 and 52. In some embodiments, the top 108 of the chair back 42 moves between 0.5 and 4 inches. In some embodiments, the top 108 of the chair back 42 moves between 1.5 and 2 inches. In some embodiments, the flex members 96 and 98 twist or rotate between 0.125 and 0.25 inches. In some embodiments, less than 5 pounds of force on the chair back 42 causes the chair back 42 to flex backward.

The first flex member 96 and the second flex member 98 elastically deflect to permit rotation of the back cross member 94 about the cross member longitudinal axis 104 as the chair back 42 moves between the upright position and the reclined position. In one aspect, the first flex member 96 is a first torsion spring that twists as the back cross member 94 rotates relative to the first side member 48 and the second side member 52, and the second flex member 98 is a second torsion spring that twists as the back cross member 94 rotates relative to the first side member 48 and the second side member 52. The first flex member 96 and the second flex member 98 cause the chair back 42 to return to the upright position from the reclined position. In some embodiments, the first flex member 96 has a flex member longitudinal axis that is parallel with the cross member longitudinal axis 104 and the first flex member 96 twists or rotates around the flex member longitudinal axis as the back cross member 94 rotates around the cross member longitudinal axis 104. In some embodiments, the second flex member 98 has a flex member longitudinal axis that is parallel with the cross member longitudinal axis 104 and the second flex member 98 twists or rotates around the flex member longitudinal axis as the back cross member 94 rotates around the cross member longitudinal axis 104.

FIG. 7 is a cross-section diagram taken along the line A-A in FIG. 6 and illustrating the chair back 42 attached to the chair back flex assembly 74, which is attached to the first side member 48 on the first side 50 of the chair 40, according to some embodiments. The front 120 of the chair 40 is at the top of FIG. 7 and the back 122 of the chair 40 is at the bottom of FIG. 7. The first side 50 of the chair 40 and the second side 54 of the chair 40 are similar, except for being mirror images of each other, such that describing the first side 50 suffices to describe the second side 54.

The chair back 42 includes the chair back frame 82 and the back support material 84. The back support material 84 is attached to the chair back frame 82, including the lower crossbar member 86, the two upright members 88 and 90, and the upper crossbar member 92. As illustrated in FIG. 7, the back support material 84 is applied across the chair back frame 82 and secured in a slot 124 of the chair back frame 82. In other embodiments, the back support material 84 can be attached to the chair back frame 82 in another suitable manner.

The chair back flex assembly 74 includes the back cross member 94 attached to the first flex member 96. The back cross member 94 is fit against the lower crossbar member 86 of the chair back frame 82, with an alignment stub 126 of the lower crossbar member 86 inserted into an alignment hole 128 of the back cross member 94. Also, the first end 100 of the back cross member 94 receives a cross member portion 96 a (also shown in FIGS. 8 and 9) of the first flex member 96.

To couple the chair back 42 to the chair back flex assembly 74 on the first side 50, a first attachment member 130 a is inserted through the upper portion 86 b (shown in FIG. 6) of the lower crossbar member 86 and through holes in the back cross member 94 and the cross member portion 96 a of the first flex member 96, before being secured to the connection block 106 a of the bottom portion 86 a (shown in FIG. 6) of the lower crossbar member 86. Also, a second attachment member 130 b is inserted through the upper portion 86 b of the lower crossbar member 86 and through holes in the back cross member 94, before being secured to the connection block 106 b of the bottom portion 86 a of the lower crossbar member 86. The first and second attachment members 130 a and 130 b and similar attachment members on the second side 54 of the chair 40 secure the chair back 42 to the chair back flex assembly 74.

To attach the chair back flex assembly 74 to the first side member 48 of the chair 40, an extension portion 96 b (also shown in FIGS. 8 and 9) of the first flex member 96 is inserted into the first leg extension 76 of the first side member 48. Fasteners (not shown in FIG. 7) are inserted through the extension portion 96 b of the first flex member 96 and secured to the first leg extension 76. The second flex member 98 is similarly secured to the second leg extension 78 on the second side 54 of the chair 40.

FIGS. 8 and 9 are diagrams illustrating the first flex member 96, according to some embodiments described in the disclosure. FIG. 8 is a diagram illustrating a perspective view of the back of the first flex member 96, according to some embodiments, and FIG. 9 is a diagram illustrating a perspective view of the front of the first flex member 96, according to some embodiments. The first flex member 96 and the second flex member 98 are similar, except for being mirror images of each other, such that describing the first flex member 96 suffices to describe the second flex member 98.

The first flex member 96 includes the cross member portion 96 a, the extension portion 96 b, and a middle portion 96 c that is between the cross member portion 96 a and the extension portion 96 b. The outer perimeter of the middle portion 96 c is larger than the outer perimeter of the cross member portion 96 a, and the outer perimeter of the middle portion 96 c is larger than the outer perimeter of the extension portion 96 b. As a result, after the cross member portion 96 a is inserted into the first end 100 of the back cross member 94 and the extension portion 96 b is inserted into the first leg extension 76, the outer perimeter of the middle portion 96 c is flush with the back cross member 94 and the first leg extension 76. Also, the middle portion 96 c is visible between the back cross member 94 and the first leg extension 76 and, in the completed chair 40, visible from the back 122 of the chair 40.

The cross member portion 96 a includes a through hole 140 that extends from the top 142 of the first flex member 96 through the bottom 144 of the first flex member 96. The attachment member 130 a is inserted through this hole 140 to couple the chair back 42 to the back cross member 94 and the first flex member 96. The cross member portion 96 a also includes two longitudinal slots 146 a and 146 b in the front of the first flex member 96. The longitudinal slots 146 a and 146 b extend longitudinally from one side 148 of the first flex member 96 to indentations 150 a and 150 b in the middle portion 96 c. The longitudinal slots 146 a and 146 b are for receiving fasteners, such as bolts, that are slid into the middle portion 96 c and the extension portion 96 b and secured to the first leg extension 76.

The middle portion 96 c and the extension portion 96 b include two longitudinal through holes 152 a and 152 b that extend from the middle portion 96 c through the other side 154 of the first flex member 96. These two holes 152 a and 152 b receive the fasteners that are inserted through the middle portion 96 c and the extension portion 96 b and secured to the first leg extension 76 to secure the first flex member 96 to the first side member 48. The heads of the fasteners, such as the heads of bolts, are situated in the longitudinal slots 146 a and 146 b of the cross member portion 96 a to hold the first flex member 96 tightly to the first leg extension 76.

The first flex member 96 is a torsion spring that twists around or about a flex member longitudinal axis 156 as the chair back 42 flexes backward. In one aspect, the first flex member 96 is a torsion bar that twists as the back cross member 94 rotates relative to the first side member 48 and the second side member 52. The flex member longitudinal axis is parallel with the longitudinal axes of the fasteners that connect the first flex member 96 to the first leg extension 76. In some embodiments, the flex member longitudinal axis 156 is parallel with the cross member longitudinal axis 104 and the first flex member 96 twists around the flex member longitudinal axis 154 as the back cross member 94 rotates around the cross member longitudinal axis 104.

In some embodiments, the first flex member 96 is formed of a substantially solid block of elastomeric material. In some embodiments, the first flex member 96 is made of at least one of rubber, urethane, and polyurethane. In some embodiments, the first flex member 96 is formed of a material having a durometer of 95 Shore A.

FIG. 10 is a diagram illustrating an enlarged front view of the first side 50 of the chair 40 without the chair back 42, according to some embodiments. As previously described, the first side 50 of the chair 40 and the second side 54 of the chair 40 are similar, except for being mirror images of each other, such that describing the first side 50 suffices to describe the second side 54.

The first side member 48 includes the first front leg 56 and the first back leg 58 connected to the first leg extension 76. The extension portion 96 b of the first flex member 96 is inserted into the first leg extension 76 and fasteners (not shown in FIG. 10) are inserted through the two holes 152 a and 152 b in the first flex member 96 and secured to the first leg extension 76. This secures the first flex member 96 to the first side member 48. The heads of the fasteners, such as the heads of bolts, are situated in the longitudinal slots 146 a and 146 b of the cross member portion 96 a to hold the first flex member 96 tightly to the first leg extension 76.

The chair back flex assembly 74 includes the first flex member 96, the second flex member 98, and the back cross member 94. The cross member portion 96 a of the first flex member 96 is inserted into the first end 100 of the back cross member 94 and the through hole 140 in the cross member portion 96 a is aligned with top and bottom holes in the back cross member 94, such as top hole 162. After the first flex member 96 has been inserted into the first leg extension 76 and the back cross member 94, the middle portion 96 c is visible between the back cross member 94 and the first leg extension 76. Also, the outer perimeter of the middle portion 96 c is flush with the back cross member 94 and the first leg extension 76.

The attachment member 130 a (shown in FIG. 7) is inserted through the upper portion 86 b of the chair back frame 82 (not shown in FIG. 10) and through the top hole 162 and a bottom hole in the back cross member 94 and the hole 140 in the first flex member 96 and secured into the connection block 106 a, to couple together the chair back 42 and the back cross member 94 and the first flex member 96 of the chair back flex assembly 74.

FIG. 11 is a diagram illustrating an enlarged back view of the first side 50 of the chair 40 including the chair back 42, according to some embodiments. As previously described, the first side 50 of the chair 40 and the second side 54 of the chair 40 are similar, except for being mirror images of each other, such that describing the first side 50 suffices to describe the second side 54.

The first side member 48 includes the first front leg 56 and the first back leg 58 connected to the first leg extension 76. The extension portion 96 b of the first flex member 96 is inserted into the first leg extension 76 and fasteners (not shown in FIG. 11) are inserted through the two holes 152 a and 152 b in the first flex member 96 and secured to the first leg extension 76. This secures the first flex member 96 to the first side member 48. The heads of the fasteners are situated in the cross member portion 96 a to hold the first flex member 96 to the first leg extension 76.

The cross member portion 96 a of the first flex member 96 is inserted into the first end 100 of the back cross member 94. The through hole 140 in the cross member portion 96 a is aligned with a hole in the upper portion 86 b of the chair back frame 82 and the top hole 162 and the bottom hole in the back cross member 94. After the first flex member 96 has been inserted into the first leg extension 76 and into the back cross member 94, the middle portion 96 c is visible between the back cross member 94 and the first leg extension 76. Also, the outer perimeter of the middle portion 96 c is flush with the back cross member 94 and the first leg extension 76.

The attachment member 130 a (shown in FIG. 7) is inserted through the hole in the upper portion 86 b and through the top hole 162 and the bottom hole in the back cross member 94 and the hole 140 in the first flex member 96 and secured into the connection block 106 a. This couples the chair back 42 to the back cross member 94 and the first flex member 96 and to the first side member 48.

FIG. 12 is a cross-section diagram of the first side 50 of the chair 40 taken along the line B-B in FIG. 11 and illustrating fasteners 164 a and 164 b securing the first flex member 96 to the first side member 48, according to some embodiments. The front 120 of the chair 40 is at the left side of FIG. 12 and the back 122 of the chair 40 is at the right side of FIG. 12. As previously described, the first side 50 of the chair 40 and the second side 54 of the chair 40 are similar, except for being mirror images of each other, such that describing the first side 50 suffices to describe the second side 54.

The back cross member 94 is a rectangular hollow tube that fits into a slot 166 in the lower crossbar member 86 of the chair back frame 82. The slot 166 is at least partially defined by the bottom portion 86 a and the upper portion 86 b of the lower crossbar member 86. The bottom portion 86 a of the lower crossbar member 86 extends below the back cross member 94 and the upper portion 86 b of the lower crossbar member 86 extends above the back cross member 94. The back support material 84 of the chair 40 is attached to the lower crossbar member 86 in front of the back cross member 94.

As shown in FIGS. 10-12, the first side member 48 includes the first front leg 56 and the first back leg 58 connected to the first leg extension 76 and the extension portion 96 b of the first flex member 96 is inserted into the first leg extension 76. The fasteners 164 a and 164 b are inserted through the two holes 152 a and 152 b in the first flex member 96 and secured to the first leg extension 76. This secures the first flex member 96 to the first side member 48. The heads of the fasteners 164 a and 164 b are situated in the longitudinal slots 146 a and 146 b of the cross member portion 96 a to hold the first flex member 96 to the first leg extension 76.

In operation, the chair back 42 is flexed from the upright position to the reclined position, such that the top 108 of the chair back 42 moves backward and the back cross member 94 rotates around or about the cross member longitudinal axis 104. The first flex member 96 twists as the back cross member 94 rotates relative to the stationary first side member 48. To help prevent further backward movement of the chair back 42 and to help prevent further rotation of the first cross member 94, the fastener 164 a engages the back cross member 94 toward the front 120 of the chair 40 and the back cross member 94, knocking against the back cross member 94 to stop rotation of the back cross member 94 and backward movement of the chair back 42.

Also, if the chair back 42 is flexed forward, such that the top 108 of the chair back 42 moves forward and the back cross member 94 rotates around or about the cross member longitudinal axis 104. To help prevent further forward movement of the chair back 42 and to help prevent further rotation of the first cross member 94, the fastener 164 b engages the back cross member 94 toward the front 120 of the chair 40 and the back cross member 94, knocking against the back cross member 94 to stop rotation of the back cross member 94 and forward movement of the chair back 42.

FIG. 13 is a cross-section diagram of the first side 50 of the chair 40 taken along the line C-C in FIG. 11 and illustrating the attachment member 130 a coupling the chair back 42 to the back cross member 94 and the first flex member 96, according to some embodiments. The front 120 of the chair 40 is at the left side of FIG. 13 and the back 122 of the chair 40 is at the right side of FIG. 13. As previously described, the first side 50 of the chair 40 and the second side 54 of the chair 40 are similar, except for being mirror images of each other, such that describing the first side 50 suffices to describe the second side 54.

The attachment member 130 a extends through a hole in the upper portion 86 b of the lower crossbar member 86, such that the head of the attachment member 130 a is situated above the upper portion 86 b. The shaft of the attachment member 130 a passes through the top hole 162 (shown in FIG. 10) and a bottom hole in the back cross member 94 and through the hole 140 (shown in FIGS. 8-10) in the cross member portion 96 a of the first flex member 96. The attachment member 130 a is secured to the connection block 106 a to couple together the chair back 42, the back cross member 94, and the first flex member 96. Also, as described above, the fasteners 164 a and 164 b are inserted through the two holes 152 a and 152 b in the first flex member 96 and secured to the first leg extension 76 to secure the first flex member 96 to the first side member 48. Thus, the chair back 42 is coupled to the back cross member 94, the first flex member 96, and the first side member 48.

In operation, the chair back 42 flexes from the upright position to the reclined position, such that the top 108 of the chair back 42 moves backward. The attachment member 130 a engages the back cross member 94 and the first flex member 96 as the chair back 42 flexes backward, and the first flex member 96 twists as the back cross member 94 rotates relative to the stationary first side member 48. The twisting first flex member 96 arrests further rotation of the back cross member 94 as it rotates relative to the first side member 48 and the second side member 52.

FIG. 14 is a cross-section diagram of the first side 50 of the chair 40 taken along the line D-D in FIG. 11 and illustrating the first front leg 56 connected to the first leg extension 76, which is attached to the first back leg 58, according to some embodiments. The front 120 of the chair 40 is at the left side of FIG. 14 and the back 122 of the chair 40 is at the right side of FIG. 14. As previously described, the first side 50 of the chair 40 and the second side 54 of the chair 40 are similar, except for being mirror images of each other, such that describing the first side 50 suffices to describe the second side 54.

The first front leg 56 is a hollow tubular member and the first leg extension 76 is inserted into one end 170 of the first front leg 56. A leg fastener 172 is connected to the first leg extension 76 and inserted inside the first front leg 56 to secure the first front leg 56 to the first leg extension 76. The fasteners 164 a and 164 b (shown in FIG. 12) are inserted through the first flex member 96 and secured to the first leg extension 76 in the holes 174 a and 174 b to secure the first flex member 96 to the first side member 48.

FIGS. 15 and 16 are diagrams illustrating the bottom of the chair 40 and support for the seat 46, according to some embodiments described in the disclosure. FIG. 15 is a diagram illustrating a bottom perspective view of the chair 40, according to some embodiments, and FIG. 16 is a diagram illustrating a bottom view of the chair 40, according to some embodiments.

The base 44 supports the chair 40 on a surface and the base 44 maintains the seat 46 and the chair back 42 off the surface. The base 44 includes the first side member 48 at the first side 50 of the chair 40 and the second side member 52 at the second side 54 of the chair 40. The first side member 48 supports the first side 50 of the chair 40 on the surface and the second side member 52 supports the second side 54 of the chair 40 on the surface. The first side member 48 includes the first front leg 56, the first back leg 58, and the first leg extension 76, and the second side member 52 includes the second front leg 60, the second back leg 62, and the second leg extension 78.

The seat 46 is coupled to the first side member 48 and the second side member 52 via the seat support assembly 72 that includes a seat cross member 180 and a seat support 182. The seat cross member 180 is attached to the first front leg 56 and the second front leg 60 and couples the first side member 48 to the second side member 52. The seat support 182 includes a U-shaped bracket 184 connected to the seat cross member 180 and a seat platform 186 rotatably connected to the U-shaped bracket 184. The seat 46 is connected to the seat platform 186, such that the seat rotates between a down, sitting position and an upright position. In the down, sitting position the seat 46 is supported by the seat cross member 180 for sitting on in the down position. The seat 46 folds from the sitting position to the upright position to save space and for storing the chair 40.

FIG. 17 is a diagram illustrating the chair 40 including the seat 46 that rotates between the down position for sitting on and the upright position for saving space and storage, indicated in dashed lines, according to some embodiments.

FIGS. 18-25 are diagrams illustrating a chair 200 that is the same as the chair 40 with the exception that the chair 200 includes a first armrest 202 and a second armrest 204, according to some embodiments described in the disclosure. As in the chair 40, the chair 200 includes the chair back 42 that has an upright position and a reclined position, illustrated in dashed lines in FIGS. 2 and 19. The chair back 42 flexes backward toward the reclined position as a user leans back in the chair 200 and the chair back 42 returns to the upright position when the user stops leaning back in the chair 200. Since the chair 200 is similar to the chair 40, the components of the chair 200 that are the same as the components of the chair 40 have like numerals. Also, to avoid being unnecessarily repetitive, the components and features of the chair 200 that have been previously described in relation to the chair 40 will not be repeated here.

FIG. 18 is a diagram illustrating a perspective view of the chair 200, according to some embodiments, and FIG. 19 is a diagram illustrating a side view of the chair 200, according to some embodiments. The first armrest 202 includes a first armrest support member 202 a and a first armrest pad member 202 b, and the second armrest 204 includes a second armrest support member 204 a and a second armrest pad member 204 b. The first armrest support member 202 a is connected to the first back leg 58 of the first side member 48 at the top of the first back leg 58, and the first armrest pad member 202 b is connected to the first armrest support member 202 a. The second armrest support member 204 a is connected to the second back leg 62 of the second side member 52 at the top of the second back leg 62, and the second armrest pad member 204 b is connected to the second armrest support member 204 a. In some embodiments, the first armrest pad member 202 b is rotatably connected to the first armrest support member 202 a to rotate into at least a partially upright vertical position. In some embodiments, the second armrest pad member 204 b is rotatably connected to the second armrest support member 204 a to rotate into at least a partially upright vertical position as indicated in dashed lines in FIG. 19.

FIG. 20 is a diagram illustrating a top view of the chair 200, according to some embodiments, FIG. 21 is a diagram illustrating a front view of the chair 200, according to some embodiments, and FIG. 22 is a diagram illustrating a back view of the chair 200, according to some embodiments. Also, FIG. 23 is a diagram illustrating a bottom perspective view of the chair 200, according to some embodiments, and FIG. 24 is a diagram illustrating a bottom view of the chair 200, according to some embodiments.

As shown in at least FIGS. 20-24, the first armrest 202 including the first armrest support member 202 a and the first armrest pad member 202 b is aligned with the first back leg 58, outside the first front leg 56 and further away from the centerline 80 than the first front leg 56. Also, the second armrest 204 including the second armrest support member 204 a and the second armrest pad member 204 b is aligned with the second back leg 62, outside the second front leg 60 and further away from the centerline 80 than the second front leg 60.

FIG. 25 is a diagram illustrating the chair 200 including the seat 46 that rotates between the down position for sitting on and the upright position for saving space and storage, indicated in dashed lines, and the first and second armrests 202 and 204 that rotate between a down position and an upright position, according to some embodiments. The second armrest pad member 204 b is rotatably connected to the second armrest support member 204 a and rotates between the down position and at least a partially vertical upright position, indicated in dashed lines in FIG. 25.

FIGS. 26 and 27 are diagrams illustrating chairs 250 stacked and aligned for storage, according to some embodiments described in the disclosure. In some embodiments, at least one of the chairs 250 is similar to chair 40. In some embodiments, at least one of the chairs 250 is similar to chair 200.

FIG. 26 is a diagram illustrating the chairs 250 stacked for storage, according to some embodiments. The chairs 250 are stacked one on top of the other with the seats, such as seat 46, in the down, sitting position. In some embodiments, the chairs 250 have armrests, such as first and second armrests 202 and 204, and the armrests are in the upright position for stacking the chairs 250.

FIG. 27 is a diagram illustrating chairs 250 aligned in a row for storage, according to some embodiments. The chairs 250 are aligned one in front of the other with the seats, such as seat 46, in the upright position. In some embodiments, the chairs 250 have armrests, such as first and second armrests 202 and 204, and the armrests are in the upright position for aligning the chairs 250 in a row.

FIG. 28 is a flowchart diagram illustrating a method of building a chair, such as chair 40 and chair 200, according to some embodiments described in the disclosure.

At 300, the method includes the step of fastening a first flex member 96 to a first side member 48 of the chair. In some embodiments, the method includes fitting an extension portion 96 b of the first flex member 96 into the first side member 48 prior to fastening the first flex member 96 to the first side member 48. In some embodiments, the method includes securing the first flex member 96 to the first leg extension 76 with fasteners, such as screws or bolts.

At 302, the method includes the step of fastening a second flex member 98 to a second side member 52 of the chair. In some embodiments, the method includes fitting an extension portion of the second flex member 98 into the second side member 52 prior to fastening the second flex member 98 to the second side member 52. In some embodiments, the method includes securing the second flex member 98 to the second leg extension 78 with fasteners, such as screws or bolts.

At 304, the method includes the step of securing the chair back 42 to the back cross member 94, where securing the chair back 42 to the back cross member 94 couples the chair back 42 to the first flex member 96 and the second flex member 98. In some embodiments, securing the chair back 42 to the back cross member 94 includes fitting or inserting a cross member portion 96 a of the first flex member 96 into one end of the back cross member 94 and inserting a cross member portion of the second flex member 98 into the other end of the back cross member 94. In some embodiments, securing the chair back 42 to the back cross member 94 includes inserting attachment members, such as the attachment member 130 a, through the upper portion 86 b of the lower crossbar member 86 of the chair back frame 82 and the back cross member 94 and the first and second flex member 96 and 98 before securing the attachment members to connection blocks, such as connection blocks 106 a and 106 d. In some embodiments, securing the chair back 42 to the back cross member 94 includes inserting attachment members, such as the attachment member 130 b, through the upper portion 86 b of the lower crossbar member 86 of the chair back frame 82 and the back cross member 94 and securing the attachment members to connection blocks, such as connection blocks 106 b and 106 c.

Various modifications and additions can be made to the exemplary embodiments discussed without departing from the scope of the present invention. For example, while the embodiments described above refer to particular features, the scope of this invention also includes embodiments having different combinations of features and embodiments that do not include all of the above described features. 

1. A chair comprising: a first side member to support a first side of the chair on a surface; a second side member to support a second side of the chair on the surface; a first cross member situated between the first side member and the second side member, the first cross member being rotatable relative to the first side member and the second side member; a first flex member coupled to the first side member and to the first cross member, the first flex member configured to twist as the first cross member rotates relative to the first side member and the second side member; and a second flex member coupled to the second side member and to the first cross member, the second flex member configured to twist as the first cross member rotates relative to the first side member and the second side member.
 2. The chair of claim 1, wherein the first flex member is a first torsion spring that twists as the first cross member rotates relative to the first side member and the second side member and the second flex member is a second torsion spring that twists as the first cross member rotates relative to the first side member and the second side member.
 3. The chair of claim 1, wherein the first cross member has a cross member longitudinal axis and the first cross member rotates relative to the first side member and the second side member around the cross member longitudinal axis.
 4. The chair of claim 3, wherein the first flex member has a flex member longitudinal axis that is parallel with the cross member longitudinal axis and the first flex member twists around the flex member longitudinal axis as the first cross member rotates around the cross member longitudinal axis.
 5. The chair of claim 1, wherein the first flex member is attached to the first side member with a fastener and the first flex member twists around a flex member longitudinal axis of the first flex member that is parallel with a longitudinal axis of the fastener.
 6. The chair of claim 1, wherein at least one of the first flex member and the second flex member is made of at least one of rubber and polyurethane.
 7. The chair of claim 1, comprising: a chair back coupled to the first cross member and having a top that moves forward and backward as the first cross member rotates relative to the first side member and the second side member.
 8. The chair of claim 1, wherein the first flex member is attached to the first side member with at least one fastener, the first flex member engaging with the at least one fastener to prevent further rotation of the first cross member as the first cross member rotates relative to the first side member and the second side member.
 9. The chair of claim 1, wherein the first flex member is coupled to the first cross member by an attachment member, the first flex member engaging with the attachment member to prevent further rotation of the first cross member as the first cross member rotates relative to the first side member and the second side member.
 10. The chair of claim 1, wherein: the first side member comprises: a first leg; and a second leg coupled to the first leg; and the second side member comprises: a third leg; and a fourth leg coupled to the third leg.
 11. The chair of claim 1, comprising: a second cross member coupled to the first side member and the second side member; a seat support connected to the second cross member; and a seat connected to the seat support to rotate between an up position and a down position, wherein the seat is supported by the second cross member for sitting on in the down position.
 12. The chair of claim 1, comprising: a first armrest coupled to the first side member; and a second armrest coupled to the second side member.
 13. A chair comprising: a first side member to support a first side of the chair on a surface; a second side member to support a second side of the chair on the surface; a first cross member situated between the first side member and the second side member, the first cross member rotatable relative to the first side member and the second side member; a first flex member secured to the first side member with at least one first fastener, the first flex member configured to deform to twist as the first cross member rotates relative to the first side member and the second side member, and the at least one first fastener to provide a first stop against the first cross member to prevent further rotation of the first cross member; and a second flex member secured to the second side member with at least one second fastener, the second flex member configured to deform to twist as the first cross member rotates relative to the first side member and the second side member, and the at least one second fastener to provide a second stop against the first cross member to prevent further rotation of the first cross member.
 14. The chair of claim 13, wherein the first flex member is a first torsion bar that twists as the first cross member rotates relative to the first side member and the second side member and the second flex member is a second torsion bar that twists as the first cross member rotates relative to the first side member and the second side member.
 15. The chair of claim 13, wherein the first flex member twists along a longitudinal axis of the first flex member that is parallel with the longitudinal axes of the at least one first fastener.
 16. The chair of claim 13, wherein at least one of the first flex member and the second flex member is made of at least one of rubber and polyurethane.
 17. The chair of claim 13, comprising: a chair back coupled to the first cross member and having a top that moves forward and backward as the first cross member rotates relative to the first side member and the second side member.
 18. The chair of claim 17, wherein the first flex member is coupled to the first cross member by an attachment member that couples the chair back to the first cross member.
 19. A method of making a chair comprising: fastening a first flex member to a first side member; fastening a second flex member to a second side member; and securing a chair back to a first cross member, wherein securing the chair back to the first cross member couples the chair back to the first flex member and the second flex member.
 20. The method of claim 19, comprising: fitting a first portion of the first flex member into the first side member prior to fastening the first flex member to the first side member.
 21. The method of claim 20, comprising: fitting a second portion of the first flex member into the first cross member prior to securing the chair back to the first cross member.
 22. The method of claim 19, wherein fastening the first flex member comprises: bolting the first flex member to the first side member.
 23. The method of claim 19, comprising: attaching a second cross member to the first side member and the second side member; and rotatably coupling a seat to the second cross member.
 24. A chair comprising: a base configured to support the chair on a surface, the base having a first side and a second side; a seat maintained by the base; a chair back having a reclined position and an upright position; and a chair back flex assembly coupling the chair back to the base, the chair back flex assembly including: a cross member having a first end and a second end and a longitudinal axis; a first flex member coupled to the cross member at the first end of the cross member such that the first flex member elastically deflects to permit rotation of the cross member about the longitudinal axis of the cross member as the chair back is moved from the upright position to the reclined position.
 25. The chair of claim 24, further comprising a second flex member coupled to the cross member at the second end of the cross member such that the second flex member elastically deflects to permit rotation of the cross member about the longitudinal axis of the cross member as the chair back is moved from the upright position to the reclined position.
 26. The chair of claim 24, wherein the first flex member is formed of a material having a durometer of 95 Shore A.
 27. The chair of claim 24, wherein the first flex member is formed of a substantially solid block of elastomeric material.
 28. The chair of claim 24, wherein the first flex member is coupled to the cross member by an attachment member, the first flex member engaging with the attachment member to arrest movement of the chair back beyond the reclined position.
 29. The chair of claim 24, wherein a portion of the first flex member is received within the cross member.
 30. The chair of claim 24, wherein the first flex member causes the chair back to return to the upright position from the reclined position. 